/* Handle exceptional things in C++.
Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- 2000, 2001 Free Software Foundation, Inc.
+ 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
Contributed by Michael Tiemann <tiemann@cygnus.com>
Rewritten by Mike Stump <mrs@cygnus.com>, based upon an
initial re-implementation courtesy Tad Hunt.
-This file is part of GNU CC.
+This file is part of GCC.
-GNU CC is free software; you can redistribute it and/or modify
+GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
-GNU CC is distributed in the hope that it will be useful,
+GCC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
-along with GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+along with GCC; see the file COPYING. If not, write to
+the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA. */
#include "config.h"
#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
#include "tree.h"
#include "rtl.h"
#include "expr.h"
#include "libfuncs.h"
#include "cp-tree.h"
#include "flags.h"
-#include "obstack.h"
#include "output.h"
#include "except.h"
#include "toplev.h"
#include "tree-inline.h"
-
-static void push_eh_cleanup PARAMS ((tree));
-static tree prepare_eh_type PARAMS ((tree));
-static tree build_eh_type_type PARAMS ((tree));
-static tree do_begin_catch PARAMS ((void));
-static int dtor_nothrow PARAMS ((tree));
-static tree do_end_catch PARAMS ((tree));
-static void push_eh_cleanup PARAMS ((tree));
-static bool decl_is_java_type PARAMS ((tree decl, int err));
-static void initialize_handler_parm PARAMS ((tree, tree));
-static tree do_allocate_exception PARAMS ((tree));
-static tree stabilize_throw_expr PARAMS ((tree, tree *));
-static tree wrap_cleanups_r PARAMS ((tree *, int *, void *));
-static int complete_ptr_ref_or_void_ptr_p PARAMS ((tree, tree));
-static bool is_admissible_throw_operand PARAMS ((tree));
-static int can_convert_eh PARAMS ((tree, tree));
-static void check_handlers_1 PARAMS ((tree, tree));
-static tree cp_protect_cleanup_actions PARAMS ((void));
+#include "tree-iterator.h"
+#include "target.h"
+
+static void push_eh_cleanup (tree);
+static tree prepare_eh_type (tree);
+static tree build_eh_type_type (tree);
+static tree do_begin_catch (void);
+static int dtor_nothrow (tree);
+static tree do_end_catch (tree);
+static bool decl_is_java_type (tree decl, int err);
+static void initialize_handler_parm (tree, tree);
+static tree do_allocate_exception (tree);
+static tree wrap_cleanups_r (tree *, int *, void *);
+static int complete_ptr_ref_or_void_ptr_p (tree, tree);
+static bool is_admissible_throw_operand (tree);
+static int can_convert_eh (tree, tree);
+static tree cp_protect_cleanup_actions (void);
/* Sets up all the global eh stuff that needs to be initialized at the
start of compilation. */
void
-init_exception_processing ()
+init_exception_processing (void)
{
tree tmp;
eh_personality_libfunc = init_one_libfunc (USING_SJLJ_EXCEPTIONS
? "__gxx_personality_sj0"
: "__gxx_personality_v0");
+ if (targetm.arm_eabi_unwinder)
+ unwind_resume_libfunc = init_one_libfunc ("__cxa_end_cleanup");
+ else
+ default_init_unwind_resume_libfunc ();
lang_eh_runtime_type = build_eh_type_type;
lang_protect_cleanup_actions = &cp_protect_cleanup_actions;
propagated out of a cleanup region. */
static tree
-cp_protect_cleanup_actions ()
+cp_protect_cleanup_actions (void)
{
/* [except.terminate]
When the destruction of an object during stack unwinding exits
using an exception ... void terminate(); is called. */
return build_call (terminate_node, NULL_TREE);
-}
+}
static tree
-prepare_eh_type (type)
- tree type;
+prepare_eh_type (tree type)
{
if (type == NULL_TREE)
return type;
return error_mark_node;
/* peel back references, so they match. */
- if (TREE_CODE (type) == REFERENCE_TYPE)
- type = TREE_TYPE (type);
+ type = non_reference (type);
/* Peel off cv qualifiers. */
type = TYPE_MAIN_VARIANT (type);
return type;
}
-/* Build the address of a typeinfo decl for use in the runtime
- matching field of the exception model. */
-
-static tree
-build_eh_type_type (type)
- tree type;
+/* Return the type info for TYPE as used by EH machinery. */
+tree
+eh_type_info (tree type)
{
tree exp;
else
exp = get_tinfo_decl (type);
+ return exp;
+}
+
+/* Build the address of a typeinfo decl for use in the runtime
+ matching field of the exception model. */
+
+static tree
+build_eh_type_type (tree type)
+{
+ tree exp = eh_type_info (type);
+
+ if (!exp)
+ return NULL;
+
mark_used (exp);
- exp = build1 (ADDR_EXPR, ptr_type_node, exp);
- return exp;
+ return convert (ptr_type_node, build_address (exp));
}
tree
-build_exc_ptr ()
+build_exc_ptr (void)
{
- return build (EXC_PTR_EXPR, ptr_type_node);
+ return build0 (EXC_PTR_EXPR, ptr_type_node);
+}
+
+/* Build up a call to __cxa_get_exception_ptr so that we can build a
+ copy constructor for the thrown object. */
+
+static tree
+do_get_exception_ptr (void)
+{
+ tree fn;
+
+ fn = get_identifier ("__cxa_get_exception_ptr");
+ if (!get_global_value_if_present (fn, &fn))
+ {
+ /* Declare void* __cxa_get_exception_ptr (void *). */
+ tree tmp = tree_cons (NULL_TREE, ptr_type_node, void_list_node);
+ fn = push_library_fn (fn, build_function_type (ptr_type_node, tmp));
+ }
+
+ return build_function_call (fn, tree_cons (NULL_TREE, build_exc_ptr (),
+ NULL_TREE));
}
/* Build up a call to __cxa_begin_catch, to tell the runtime that the
exception has been handled. */
static tree
-do_begin_catch ()
+do_begin_catch (void)
{
tree fn;
fn = get_identifier ("__cxa_begin_catch");
- if (IDENTIFIER_GLOBAL_VALUE (fn))
- fn = IDENTIFIER_GLOBAL_VALUE (fn);
- else
+ if (!get_global_value_if_present (fn, &fn))
{
/* Declare void* __cxa_begin_catch (void *). */
tree tmp = tree_cons (NULL_TREE, ptr_type_node, void_list_node);
NULL_TREE for a ... handler) will not throw an exception. */
static int
-dtor_nothrow (type)
- tree type;
+dtor_nothrow (tree type)
{
- tree fn;
-
if (type == NULL_TREE)
return 0;
- if (! TYPE_HAS_DESTRUCTOR (type))
+ if (!CLASS_TYPE_P (type))
return 1;
- fn = lookup_member (type, dtor_identifier, 0, 0);
- fn = TREE_VALUE (fn);
- return TREE_NOTHROW (fn);
+ if (CLASSTYPE_LAZY_DESTRUCTOR (type))
+ lazily_declare_fn (sfk_destructor, type);
+
+ return TREE_NOTHROW (CLASSTYPE_DESTRUCTORS (type));
}
/* Build up a call to __cxa_end_catch, to destroy the exception object
for the current catch block if no others are currently using it. */
static tree
-do_end_catch (type)
- tree type;
+do_end_catch (tree type)
{
tree fn, cleanup;
fn = get_identifier ("__cxa_end_catch");
- if (IDENTIFIER_GLOBAL_VALUE (fn))
- fn = IDENTIFIER_GLOBAL_VALUE (fn);
- else
+ if (!get_global_value_if_present (fn, &fn))
{
/* Declare void __cxa_end_catch (). */
fn = push_void_library_fn (fn, void_list_node);
/* This routine creates the cleanup for the current exception. */
static void
-push_eh_cleanup (type)
- tree type;
+push_eh_cleanup (tree type)
{
finish_decl_cleanup (NULL_TREE, do_end_catch (type));
}
throw. */
static bool
-decl_is_java_type (decl, err)
- tree decl;
- int err;
+decl_is_java_type (tree decl, int err)
{
bool r = (TREE_CODE (decl) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
&& TYPE_FOR_JAVA (TREE_TYPE (decl)))
{
/* Can't throw a reference. */
- error ("type `%T' is disallowed in Java `throw' or `catch'",
- decl);
+ error ("type %qT is disallowed in Java %<throw%> or %<catch%>",
+ decl);
}
if (r)
if (jthrow_node == NULL_TREE)
fatal_error
- ("call to Java `catch' or `throw' with `jthrowable' undefined");
+ ("call to Java %<catch%> or %<throw%> with %<jthrowable%> undefined");
jthrow_node = TREE_TYPE (TREE_TYPE (jthrow_node));
if (! DERIVED_FROM_P (jthrow_node, TREE_TYPE (decl)))
{
/* Thrown object must be a Throwable. */
- error ("type `%T' is not derived from `java::lang::Throwable'",
- TREE_TYPE (decl));
+ error ("type %qT is not derived from %<java::lang::Throwable%>",
+ TREE_TYPE (decl));
}
}
}
__gxx_personality_(sj|v)0 in init_exception_processing - should it
be done here instead? */
void
-choose_personality_routine (lang)
- enum languages lang;
+choose_personality_routine (enum languages lang)
{
static enum {
chose_none,
return;
case chose_none:
- ; /* proceed to language selection */
+ ; /* Proceed to language selection. */
}
switch (lang)
break;
default:
- abort ();
+ gcc_unreachable ();
}
return;
/* Initialize the catch parameter DECL. */
-static void
-initialize_handler_parm (decl, exp)
- tree decl;
- tree exp;
+static void
+initialize_handler_parm (tree decl, tree exp)
{
tree init;
tree init_type;
TREE_USED (decl) = 1;
/* Figure out the type that the initializer is. Pointers are returned
- adjusted by value from __cxa_begin_catch. Others are returned by
+ adjusted by value from __cxa_begin_catch. Others are returned by
reference. */
init_type = TREE_TYPE (decl);
- if (! TYPE_PTR_P (init_type)
- && TREE_CODE (init_type) != REFERENCE_TYPE)
+ if (!POINTER_TYPE_P (init_type))
init_type = build_reference_type (init_type);
choose_personality_routine (decl_is_java_type (init_type, 0)
init = build1 (MUST_NOT_THROW_EXPR, TREE_TYPE (init), init);
}
- /* Let `cp_finish_decl' know that this initializer is ok. */
- DECL_INITIAL (decl) = error_mark_node;
decl = pushdecl (decl);
- start_decl_1 (decl);
- cp_finish_decl (decl, init, NULL_TREE,
+ start_decl_1 (decl, true);
+ cp_finish_decl (decl, init, /*init_const_expr_p=*/false, NULL_TREE,
LOOKUP_ONLYCONVERTING|DIRECT_BIND);
}
/* Call this to start a catch block. DECL is the catch parameter. */
tree
-expand_start_catch_block (decl)
- tree decl;
+expand_start_catch_block (tree decl)
{
- tree exp = NULL_TREE;
+ tree exp;
tree type;
- bool is_java;
if (! doing_eh (1))
return NULL_TREE;
/* Make sure this declaration is reasonable. */
if (decl && !complete_ptr_ref_or_void_ptr_p (TREE_TYPE (decl), NULL_TREE))
- decl = NULL_TREE;
+ decl = error_mark_node;
if (decl)
type = prepare_eh_type (TREE_TYPE (decl));
else
type = NULL_TREE;
- is_java = false;
- if (decl)
+ if (decl && decl_is_java_type (type, 1))
{
- tree init;
-
- if (decl_is_java_type (type, 1))
- {
- /* Java only passes object via pointer and doesn't require
- adjusting. The java object is immediately before the
- generic exception header. */
- init = build_exc_ptr ();
- init = build1 (NOP_EXPR, build_pointer_type (type), init);
- init = build (MINUS_EXPR, TREE_TYPE (init), init,
- TYPE_SIZE_UNIT (TREE_TYPE (init)));
- init = build_indirect_ref (init, NULL);
- is_java = true;
- }
- else
- {
- /* C++ requires that we call __cxa_begin_catch to get the
- pointer to the actual object. */
- init = do_begin_catch ();
- }
-
- exp = create_temporary_var (ptr_type_node);
- DECL_REGISTER (exp) = 1;
- cp_finish_decl (exp, init, NULL_TREE, LOOKUP_ONLYCONVERTING);
- finish_expr_stmt (build_modify_expr (exp, INIT_EXPR, init));
+ /* Java only passes object via pointer and doesn't require
+ adjusting. The java object is immediately before the
+ generic exception header. */
+ exp = build_exc_ptr ();
+ exp = build1 (NOP_EXPR, build_pointer_type (type), exp);
+ exp = build2 (MINUS_EXPR, TREE_TYPE (exp), exp,
+ TYPE_SIZE_UNIT (TREE_TYPE (exp)));
+ exp = build_indirect_ref (exp, NULL);
+ initialize_handler_parm (decl, exp);
+ return type;
}
- else
+
+ /* Call __cxa_end_catch at the end of processing the exception. */
+ push_eh_cleanup (type);
+
+ /* If there's no decl at all, then all we need to do is make sure
+ to tell the runtime that we've begun handling the exception. */
+ if (decl == NULL || decl == error_mark_node)
finish_expr_stmt (do_begin_catch ());
- /* C++ requires that we call __cxa_end_catch at the end of
- processing the exception. */
- if (! is_java)
- push_eh_cleanup (type);
+ /* If the C++ object needs constructing, we need to do that before
+ calling __cxa_begin_catch, so that std::uncaught_exception gets
+ the right value during the copy constructor. */
+ else if (flag_use_cxa_get_exception_ptr
+ && TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl)))
+ {
+ exp = do_get_exception_ptr ();
+ initialize_handler_parm (decl, exp);
+ finish_expr_stmt (do_begin_catch ());
+ }
- if (decl)
- initialize_handler_parm (decl, exp);
+ /* Otherwise the type uses a bitwise copy, and we don't have to worry
+ about the value of std::uncaught_exception and therefore can do the
+ copy with the return value of __cxa_end_catch instead. */
+ else
+ {
+ tree init = do_begin_catch ();
+ tree init_type = type;
+
+ /* Pointers are passed by values, everything else by reference. */
+ if (!TYPE_PTR_P (type))
+ init_type = build_pointer_type (type);
+ if (init_type != TREE_TYPE (init))
+ init = build1 (NOP_EXPR, init_type, init);
+ exp = create_temporary_var (init_type);
+ DECL_REGISTER (exp) = 1;
+ cp_finish_decl (exp, init, /*init_const_expr=*/false,
+ NULL_TREE, LOOKUP_ONLYCONVERTING);
+ initialize_handler_parm (decl, exp);
+ }
return type;
}
the label to jump to if this catch block didn't match. */
void
-expand_end_catch_block ()
+expand_end_catch_block (void)
{
if (! doing_eh (1))
return;
}
tree
-begin_eh_spec_block ()
+begin_eh_spec_block (void)
{
tree r = build_stmt (EH_SPEC_BLOCK, NULL_TREE, NULL_TREE);
add_stmt (r);
+ EH_SPEC_STMTS (r) = push_stmt_list ();
return r;
}
void
-finish_eh_spec_block (raw_raises, eh_spec_block)
- tree raw_raises;
- tree eh_spec_block;
+finish_eh_spec_block (tree raw_raises, tree eh_spec_block)
{
tree raises;
- RECHAIN_STMTS (eh_spec_block, EH_SPEC_STMTS (eh_spec_block));
+ EH_SPEC_STMTS (eh_spec_block) = pop_stmt_list (EH_SPEC_STMTS (eh_spec_block));
/* Strip cv quals, etc, from the specification types. */
for (raises = NULL_TREE;
raw_raises && TREE_VALUE (raw_raises);
raw_raises = TREE_CHAIN (raw_raises))
- raises = tree_cons (NULL_TREE, prepare_eh_type (TREE_VALUE (raw_raises)),
- raises);
+ {
+ tree type = prepare_eh_type (TREE_VALUE (raw_raises));
+ tree tinfo = eh_type_info (type);
+
+ mark_used (tinfo);
+ raises = tree_cons (NULL_TREE, type, raises);
+ }
EH_SPEC_RAISES (eh_spec_block) = raises;
}
/* Return a pointer to a buffer for an exception object of type TYPE. */
static tree
-do_allocate_exception (type)
- tree type;
+do_allocate_exception (tree type)
{
tree fn;
fn = get_identifier ("__cxa_allocate_exception");
- if (IDENTIFIER_GLOBAL_VALUE (fn))
- fn = IDENTIFIER_GLOBAL_VALUE (fn);
- else
+ if (!get_global_value_if_present (fn, &fn))
{
/* Declare void *__cxa_allocate_exception(size_t). */
- tree tmp = tree_cons (NULL_TREE, c_size_type_node, void_list_node);
+ tree tmp = tree_cons (NULL_TREE, size_type_node, void_list_node);
fn = push_library_fn (fn, build_function_type (ptr_type_node, tmp));
}
-
+
return build_function_call (fn, tree_cons (NULL_TREE, size_in_bytes (type),
NULL_TREE));
}
-#if 0
/* Call __cxa_free_exception from a cleanup. This is never invoked
directly, but see the comment for stabilize_throw_expr. */
static tree
-do_free_exception (ptr)
- tree ptr;
+do_free_exception (tree ptr)
{
tree fn;
fn = get_identifier ("__cxa_free_exception");
- if (IDENTIFIER_GLOBAL_VALUE (fn))
- fn = IDENTIFIER_GLOBAL_VALUE (fn);
- else
+ if (!get_global_value_if_present (fn, &fn))
{
/* Declare void __cxa_free_exception (void *). */
fn = push_void_library_fn (fn, tree_cons (NULL_TREE, ptr_type_node,
return build_function_call (fn, tree_cons (NULL_TREE, ptr, NULL_TREE));
}
-#endif
/* Wrap all cleanups for TARGET_EXPRs in MUST_NOT_THROW_EXPR.
Called from build_throw via walk_tree_without_duplicates. */
static tree
-wrap_cleanups_r (tp, walk_subtrees, data)
- tree *tp;
- int *walk_subtrees ATTRIBUTE_UNUSED;
- void *data ATTRIBUTE_UNUSED;
+wrap_cleanups_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
+ void *data ATTRIBUTE_UNUSED)
{
tree exp = *tp;
tree cleanup;
cleanup = TARGET_EXPR_CLEANUP (exp);
if (cleanup)
{
- cleanup = build1 (MUST_NOT_THROW_EXPR, TREE_TYPE (cleanup), cleanup);
+ cleanup = build1 (MUST_NOT_THROW_EXPR, void_type_node, cleanup);
TARGET_EXPR_CLEANUP (exp) = cleanup;
}
return NULL_TREE;
}
-/* Like stabilize_expr, but specifically for a thrown expression. When
- throwing a temporary class object, we want to construct it directly into
- the thrown exception, so we look past the TARGET_EXPR and stabilize the
- arguments of the call instead.
-
- The case where EXP is a call to a function returning a class is a bit of
- a grey area in the standard; it's unclear whether or not it should be
- allowed to throw. I'm going to say no, as that allows us to optimize
- this case without worrying about deallocating the exception object if it
- does. The alternatives would be either not optimizing this case, or
- wrapping the initialization in a TRY_CATCH_EXPR to call do_free_exception
- rather than in a MUST_NOT_THROW_EXPR, for this case only. */
-
-static tree
-stabilize_throw_expr (exp, initp)
- tree exp;
- tree *initp;
-{
- tree init_expr;
-
- if (TREE_CODE (exp) == TARGET_EXPR
- && TREE_CODE (TARGET_EXPR_INITIAL (exp)) == AGGR_INIT_EXPR
- && flag_elide_constructors)
- {
- tree aggr_init = AGGR_INIT_EXPR_CHECK (TARGET_EXPR_INITIAL (exp));
- tree args = TREE_OPERAND (aggr_init, 1);
- tree newargs = NULL_TREE;
- tree *p = &newargs;
-
- init_expr = void_zero_node;
- for (; args; args = TREE_CHAIN (args))
- {
- tree arg_init_expr;
- tree newarg = stabilize_expr (TREE_VALUE (args), &arg_init_expr);
-
- if (arg_init_expr != void_zero_node)
- init_expr = build (COMPOUND_EXPR, void_type_node, arg_init_expr, init_expr);
- *p = tree_cons (NULL_TREE, newarg, NULL_TREE);
- p = &TREE_CHAIN (*p);
- }
- TREE_OPERAND (aggr_init, 1) = newargs;
- }
- else
- {
- exp = stabilize_expr (exp, &init_expr);
- }
-
- *initp = init_expr;
- return exp;
-}
-
/* Build a throw expression. */
tree
-build_throw (exp)
- tree exp;
+build_throw (tree exp)
{
tree fn;
return exp;
if (processing_template_decl)
- return build_min (THROW_EXPR, void_type_node, exp);
+ {
+ if (cfun)
+ current_function_returns_abnormally = 1;
+ return build_min (THROW_EXPR, void_type_node, exp);
+ }
if (exp == null_node)
- warning ("throwing NULL, which has integral, not pointer type");
-
+ warning (0, "throwing NULL, which has integral, not pointer type");
+
if (exp != NULL_TREE)
{
if (!is_admissible_throw_operand (exp))
- return error_mark_node;
+ return error_mark_node;
}
if (! doing_eh (1))
if (exp && decl_is_java_type (TREE_TYPE (exp), 1))
{
tree fn = get_identifier ("_Jv_Throw");
- if (IDENTIFIER_GLOBAL_VALUE (fn))
- fn = IDENTIFIER_GLOBAL_VALUE (fn);
- else
+ if (!get_global_value_if_present (fn, &fn))
{
/* Declare void _Jv_Throw (void *). */
tree tmp = tree_cons (NULL_TREE, ptr_type_node, void_list_node);
tmp = build_function_type (ptr_type_node, tmp);
fn = push_throw_library_fn (fn, tmp);
}
-
+ else if (really_overloaded_fn (fn))
+ {
+ error ("%qD should never be overloaded", fn);
+ return error_mark_node;
+ }
+ fn = OVL_CURRENT (fn);
exp = build_function_call (fn, tree_cons (NULL_TREE, exp, NULL_TREE));
}
else if (exp)
{
tree throw_type;
+ tree temp_type;
tree cleanup;
tree object, ptr;
tree tmp;
tree temp_expr, allocate_expr;
+ bool elided;
- fn = get_identifier ("__cxa_throw");
- if (IDENTIFIER_GLOBAL_VALUE (fn))
- fn = IDENTIFIER_GLOBAL_VALUE (fn);
- else
+ /* The CLEANUP_TYPE is the internal type of a destructor. */
+ if (!cleanup_type)
{
- /* The CLEANUP_TYPE is the internal type of a destructor. */
- if (cleanup_type == NULL_TREE)
- {
- tmp = void_list_node;
- tmp = tree_cons (NULL_TREE, ptr_type_node, tmp);
- tmp = build_function_type (void_type_node, tmp);
- cleanup_type = build_pointer_type (tmp);
- }
+ tmp = void_list_node;
+ tmp = tree_cons (NULL_TREE, ptr_type_node, tmp);
+ tmp = build_function_type (void_type_node, tmp);
+ cleanup_type = build_pointer_type (tmp);
+ }
+ fn = get_identifier ("__cxa_throw");
+ if (!get_global_value_if_present (fn, &fn))
+ {
/* Declare void __cxa_throw (void*, void*, void (*)(void*)). */
/* ??? Second argument is supposed to be "std::type_info*". */
tmp = void_list_node;
fn = push_throw_library_fn (fn, tmp);
}
- /* throw expression */
- /* First, decay it. */
- exp = decay_conversion (exp);
+ /* [except.throw]
+
+ A throw-expression initializes a temporary object, the type
+ of which is determined by removing any top-level
+ cv-qualifiers from the static type of the operand of throw
+ and adjusting the type from "array of T" or "function return
+ T" to "pointer to T" or "pointer to function returning T"
+ respectively. */
+ temp_type = is_bitfield_expr_with_lowered_type (exp);
+ if (!temp_type)
+ temp_type = type_decays_to (TYPE_MAIN_VARIANT (TREE_TYPE (exp)));
/* OK, this is kind of wacky. The standard says that we call
terminate when the exception handling mechanism, after
the call to __cxa_allocate_exception first (which doesn't
matter, since it can't throw). */
- /* Pre-evaluate the thrown expression first, since if we allocated
- the space first we would have to deal with cleaning it up if
- evaluating this expression throws. */
- exp = stabilize_throw_expr (exp, &temp_expr);
-
/* Allocate the space for the exception. */
- allocate_expr = do_allocate_exception (TREE_TYPE (exp));
+ allocate_expr = do_allocate_exception (temp_type);
allocate_expr = get_target_expr (allocate_expr);
ptr = TARGET_EXPR_SLOT (allocate_expr);
- object = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (exp)), ptr);
+ object = build_nop (build_pointer_type (temp_type), ptr);
object = build_indirect_ref (object, NULL);
+ elided = (TREE_CODE (exp) == TARGET_EXPR);
+
/* And initialize the exception object. */
- exp = build_init (object, exp, LOOKUP_ONLYCONVERTING);
- if (exp == error_mark_node)
+ if (CLASS_TYPE_P (temp_type))
{
- error (" in thrown expression");
- return error_mark_node;
+ /* Call the copy constructor. */
+ exp = (build_special_member_call
+ (object, complete_ctor_identifier,
+ build_tree_list (NULL_TREE, exp),
+ TREE_TYPE (object),
+ LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING));
+ if (exp == error_mark_node)
+ {
+ error (" in thrown expression");
+ return error_mark_node;
+ }
}
+ else
+ exp = build2 (INIT_EXPR, temp_type, object,
+ decay_conversion (exp));
+
+ /* Pre-evaluate the thrown expression first, since if we allocated
+ the space first we would have to deal with cleaning it up if
+ evaluating this expression throws.
+
+ The case where EXP the initializer is a cast or a function
+ returning a class is a bit of a grey area in the standard; it's
+ unclear whether or not it should be allowed to throw. We used to
+ say no, as that allowed us to optimize this case without worrying
+ about deallocating the exception object if it does. But that
+ conflicted with expectations (PR 13944) and the EDG compiler; now
+ we wrap the initialization in a TRY_CATCH_EXPR to call
+ do_free_exception rather than in a MUST_NOT_THROW_EXPR, for this
+ case only.
+
+ BUT: Issue 475 may do away with this inconsistency by removing the
+ terminate() in this situation.
+
+ Note that we don't check the return value from stabilize_init
+ because it will only return false in cases where elided is true,
+ and therefore we don't need to work around the failure to
+ preevaluate. */
+ temp_expr = NULL_TREE;
+ stabilize_init (exp, &temp_expr);
+
+ /* Wrap the initialization in a CLEANUP_POINT_EXPR so that cleanups
+ for temporaries within the initialization are run before the one
+ for the exception object, preserving LIFO order. */
+ exp = build1 (CLEANUP_POINT_EXPR, void_type_node, exp);
+
+ if (elided)
+ exp = build2 (TRY_CATCH_EXPR, void_type_node, exp,
+ do_free_exception (ptr));
+ else
+ exp = build1 (MUST_NOT_THROW_EXPR, void_type_node, exp);
- exp = build1 (MUST_NOT_THROW_EXPR, TREE_TYPE (exp), exp);
/* Prepend the allocation. */
- exp = build (COMPOUND_EXPR, TREE_TYPE (exp), allocate_expr, exp);
- if (temp_expr != void_zero_node)
+ exp = build2 (COMPOUND_EXPR, TREE_TYPE (exp), allocate_expr, exp);
+ if (temp_expr)
{
/* Prepend the calculation of the throw expression. Also, force
any cleanups from the expression to be evaluated here so that
them in MUST_NOT_THROW_EXPR, since they are run after the
exception object is initialized. */
walk_tree_without_duplicates (&temp_expr, wrap_cleanups_r, 0);
- exp = build (COMPOUND_EXPR, TREE_TYPE (exp), temp_expr, exp);
+ exp = build2 (COMPOUND_EXPR, TREE_TYPE (exp), temp_expr, exp);
exp = build1 (CLEANUP_POINT_EXPR, TREE_TYPE (exp), exp);
}
throw_type = build_eh_type_type (prepare_eh_type (TREE_TYPE (object)));
- if (TYPE_HAS_DESTRUCTOR (TREE_TYPE (object)))
+ if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (object)))
{
cleanup = lookup_fnfields (TYPE_BINFO (TREE_TYPE (object)),
complete_dtor_identifier, 0);
- cleanup = TREE_VALUE (cleanup);
+ cleanup = BASELINK_FUNCTIONS (cleanup);
mark_used (cleanup);
- mark_addressable (cleanup);
+ cxx_mark_addressable (cleanup);
/* Pretend it's a normal function. */
cleanup = build1 (ADDR_EXPR, cleanup_type, cleanup);
}
else
- {
- cleanup = build_int_2 (0, 0);
- TREE_TYPE (cleanup) = cleanup_type;
- }
+ cleanup = build_int_cst (cleanup_type, 0);
tmp = tree_cons (NULL_TREE, cleanup, NULL_TREE);
tmp = tree_cons (NULL_TREE, throw_type, tmp);
tmp = build_function_call (fn, tmp);
/* Tack on the initialization stuff. */
- exp = build (COMPOUND_EXPR, TREE_TYPE (tmp), exp, tmp);
+ exp = build2 (COMPOUND_EXPR, TREE_TYPE (tmp), exp, tmp);
}
else
{
/* Rethrow current exception. */
tree fn = get_identifier ("__cxa_rethrow");
- if (IDENTIFIER_GLOBAL_VALUE (fn))
- fn = IDENTIFIER_GLOBAL_VALUE (fn);
- else
+ if (!get_global_value_if_present (fn, &fn))
{
/* Declare void __cxa_rethrow (void). */
fn = push_throw_library_fn
}
/* ??? Indicate that this function call allows exceptions of the type
- of the enclosing catch block (if known). */
+ of the enclosing catch block (if known). */
exp = build_function_call (fn, NULL_TREE);
}
/* Make sure TYPE is complete, pointer to complete, reference to
complete, or pointer to cv void. Issue diagnostic on failure.
- Return the zero on failure and non-zero on success. FROM can be
+ Return the zero on failure and nonzero on success. FROM can be
the expr or decl from whence TYPE came, if available. */
static int
-complete_ptr_ref_or_void_ptr_p (type, from)
- tree type;
- tree from;
+complete_ptr_ref_or_void_ptr_p (tree type, tree from)
{
int is_ptr;
-
+
/* Check complete. */
type = complete_type_or_else (type, from);
if (!type)
return 0;
-
+
/* Or a pointer or ref to one, or cv void *. */
is_ptr = TREE_CODE (type) == POINTER_TYPE;
if (is_ptr || TREE_CODE (type) == REFERENCE_TYPE)
{
tree core = TREE_TYPE (type);
-
+
if (is_ptr && VOID_TYPE_P (core))
- /* OK */;
+ /* OK */;
else if (!complete_type_or_else (core, from))
- return 0;
+ return 0;
}
return 1;
}
a type or of an abstract class type. */
static bool
-is_admissible_throw_operand (expr)
- tree expr;
+is_admissible_throw_operand (tree expr)
{
tree type = TREE_TYPE (expr);
/* 15.1/4 [...] The type of the throw-expression shall not be an
- incomplete type, or a pointer or a reference to an incomplete
- type, other than void*, const void*, volatile void*, or
- const volatile void*. Except for these restriction and the
- restrictions on type matching mentioned in 15.3, the operand
- of throw is treated exactly as a function argument in a call
- (5.2.2) or the operand of a return statement. */
+ incomplete type, or a pointer or a reference to an incomplete
+ type, other than void*, const void*, volatile void*, or
+ const volatile void*. Except for these restriction and the
+ restrictions on type matching mentioned in 15.3, the operand
+ of throw is treated exactly as a function argument in a call
+ (5.2.2) or the operand of a return statement. */
if (!complete_ptr_ref_or_void_ptr_p (type, expr))
return false;
/* 10.4/3 An abstract class shall not be used as a parameter type,
- as a function return type or as type of an explicit
- conversion. */
+ as a function return type or as type of an explicit
+ conversion. */
else if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
{
- error ("expression '%E' of abstract class type '%T' cannot be used in throw-expression", expr, type);
+ error ("expression %qE of abstract class type %qT cannot "
+ "be used in throw-expression", expr, type);
return false;
}
#include "cfns.h"
int
-nothrow_libfn_p (fn)
- tree fn;
+nothrow_libfn_p (tree fn)
{
tree id;
/* Can't be a C library function. */
return 0;
- id = DECL_ASSEMBLER_NAME (fn);
+ /* Being a C library function, DECL_ASSEMBLER_NAME == DECL_NAME
+ unless the system headers are playing rename tricks, and if
+ they are, we don't want to be confused by them. */
+ id = DECL_NAME (fn);
return !!libc_name_p (IDENTIFIER_POINTER (id), IDENTIFIER_LENGTH (id));
}
handler for type TO, as per [except.handle]. */
static int
-can_convert_eh (to, from)
- tree to, from;
+can_convert_eh (tree to, tree from)
{
- if (TREE_CODE (to) == REFERENCE_TYPE)
- to = TREE_TYPE (to);
- if (TREE_CODE (from) == REFERENCE_TYPE)
- from = TREE_TYPE (from);
+ to = non_reference (to);
+ from = non_reference (from);
if (TREE_CODE (to) == POINTER_TYPE && TREE_CODE (from) == POINTER_TYPE)
{
if (TREE_CODE (to) == VOID_TYPE)
return 1;
- /* else fall through */
+ /* Else fall through. */
}
if (CLASS_TYPE_P (to) && CLASS_TYPE_P (from)
return 0;
}
-/* Check whether any of HANDLERS are shadowed by another handler accepting
- TYPE. Note that the shadowing may not be complete; even if an exception
- of type B would be caught by a handler for A, there could be a derived
- class C for which A is an ambiguous base but B is not, so the handler
- for B would catch an exception of type C. */
+/* Check whether any of the handlers in I are shadowed by another handler
+ accepting TYPE. Note that the shadowing may not be complete; even if
+ an exception of type B would be caught by a handler for A, there could
+ be a derived class C for which A is an ambiguous base but B is not, so
+ the handler for B would catch an exception of type C. */
static void
-check_handlers_1 (master, handlers)
- tree master;
- tree handlers;
+check_handlers_1 (tree master, tree_stmt_iterator i)
{
tree type = TREE_TYPE (master);
- tree handler;
- for (handler = handlers; handler; handler = TREE_CHAIN (handler))
- if (TREE_TYPE (handler)
- && can_convert_eh (type, TREE_TYPE (handler)))
- {
- lineno = STMT_LINENO (handler);
- warning ("exception of type `%T' will be caught",
- TREE_TYPE (handler));
- lineno = STMT_LINENO (master);
- warning (" by earlier handler for `%T'", type);
- break;
- }
+ for (; !tsi_end_p (i); tsi_next (&i))
+ {
+ tree handler = tsi_stmt (i);
+ if (TREE_TYPE (handler) && can_convert_eh (type, TREE_TYPE (handler)))
+ {
+ warning (0, "%Hexception of type %qT will be caught",
+ EXPR_LOCUS (handler), TREE_TYPE (handler));
+ warning (0, "%H by earlier handler for %qT",
+ EXPR_LOCUS (master), type);
+ break;
+ }
+ }
}
-/* Given a chain of HANDLERs, make sure that they're OK. */
+/* Given a STATEMENT_LIST of HANDLERs, make sure that they're OK. */
void
-check_handlers (handlers)
- tree handlers;
+check_handlers (tree handlers)
{
- tree handler;
- int save_line = lineno;
- for (handler = handlers; handler; handler = TREE_CHAIN (handler))
- {
- if (TREE_CHAIN (handler) == NULL_TREE)
- /* No more handlers; nothing to shadow. */;
- else if (TREE_TYPE (handler) == NULL_TREE)
- {
- lineno = STMT_LINENO (handler);
- pedwarn
- ("`...' handler must be the last handler for its try block");
- }
- else
- check_handlers_1 (handler, TREE_CHAIN (handler));
- }
- lineno = save_line;
+ tree_stmt_iterator i;
+
+ /* If we don't have a STATEMENT_LIST, then we've just got one
+ handler, and thus nothing to warn about. */
+ if (TREE_CODE (handlers) != STATEMENT_LIST)
+ return;
+
+ i = tsi_start (handlers);
+ if (!tsi_end_p (i))
+ while (1)
+ {
+ tree handler = tsi_stmt (i);
+ tsi_next (&i);
+
+ /* No more handlers; nothing to shadow. */
+ if (tsi_end_p (i))
+ break;
+ if (TREE_TYPE (handler) == NULL_TREE)
+ pedwarn ("%H%<...%> handler must be the last handler for"
+ " its try block", EXPR_LOCUS (handler));
+ else
+ check_handlers_1 (handler, i);
+ }
}